Since its creation in 1988, the Intergovernmental Panel on Climate Change (IPCC, or The Panel) has been the leading scientific body on climate change. It was created to find just cause for proliferating nuclear energy in the United Kingdom to reduce dependency on oil from the Middle East and coal from fickle coal workers. To do this, it would need to determine the extent that human activity is responsible for global warming.
This goal is pursued by periodically preparing comprehensive Assessment Reports about climate. The IPCC’s reports, of which there have been four, are the most cited and most influential documents in climatology. Its recommendations to legislators and public officials are behind many policies (e.g., cap-and-trade) and the global climate change political movement.
Many such policies acknowledge that there continues to be significant uncertainty about the exact scope and timing of climate change-related impacts. Despite these uncertainties, they propose moving forward with goals and response actions justified on a set of assumptions taken from IPCC reports. However, such policies unduly take these assumptions to be the scientific consensus.
Members of the scientific community, some of whom contributed to the Panel’s Assessment Reports, continue to refute some of its findings and each of the IPCC’s reports has been met with controversy. Controversies have ranged from scientists claiming that the reports have been tainted by political motivation, to abuse of the peer-review system, and finally, to the use of specious data. All of these things debase the models used by the IPCC and render its recommendations questionable. .
Rather than making overt affronts on the IPCC, other scientists have simply and astutely pointed out that if the climate’s fundamental dynamics are not completely understood then the models will therefore also be incomplete, possibly inaccurate.
The Panel’s reports should not be taken as gospel, but rather as evolving works in progress. As such, the findings should be viewed as inconclusive and incomplete.
Well-informed policies are effective policies and the policies implemented today should not be based on science that will be understood tomorrow. There remain principal gaps and limitations in what is understood and what can be modeled by climatologists. And until these gaps can be filled we should not be precipitous in our actions. For the costs of ill-advised or ill-directed actions may very well outweigh those of inaction.
Three of the principal gaps in climatology today are: (1) Scientific understanding of climate science; (2) Modeling systems are most reliable on large geographic scales and unreliable on smaller scales; and (3) Modeling capabilities are constrained by computing capability.
Gaps in scientific understanding of climate science
There are many interrelated elements that contribute to the Earth’s climate which makes understanding it difficult and complex. Some of these elements include: The occurrence of sun spots, the number of trees, ocean temperature, desertification, cloud cover, the list goes on. The IPCC model attempts to quantify and properly weight the importance of these variables to make its predictions. To illustrate the complexity of the climate system and the difficulty of reducing it to an algorithm consider the following. A “+” signifies a temperature increase and “-” signifies a decrease.
- An increase in the concentration of CO2 in the Earth’s atmosphere traps solar radiation that would otherwise be reflected back into outer space. ( + )
- As the temperature increases, the rate of evaporation increases which leads to the formation of more clouds. More clouds means more solar radiation get reflected back into space. ( - )
- However, with more cloud cover comes more rain and more trees. Since trees cannot use all of the water they absorb, more water is returned to the skies and leads to the creation of clouds. ( - ) Also, more trees equates to more CO2 being absorbed. ( - )
- But trees have a relatively high Albedo Effect, i.e., they absorb heat. ( + ).
This example, though crude, illustrates that reliance on one variable is insufficient to make even general statements about the climate’s behavior.
There are also low-frequency variables purported to be indicative of climate change such as hurricanes and El Niño that are even less understood. This further limits the confidence that can be placed on the ability of climate models to realistically simulate the climate.
Insufficient research has also been conducted to allow climatologists to delineate clearly between the anthropogenic climate-changing variables and those that occur naturally. This brings into question the fundamental assumption of the IPCC: climate is being driven by human activities.
The IPCC has relied heavily upon the graph to the right.[1] The graph illustrates that since circa 1850, the global average temperature has risen to its highest level in a millennium and, that the timing of this increase coincides with industrial expansion, ergo, more GHG emissions.
For example, as the graph indicates, the increase in temperatures sharply increased between 1850 and 1940. Though many processes were industrialized, the world economy was not in full swing. In fact, there was a lengthy global recession in the 1930s. But, when widespread economic activity began post-World War II, the temperature dipped for several years before increasing again circa 1975. This is inconsistent with the theory that increased carbon concentration warms the planet.
This has led many in the scientific community to question whether GHGs are in fact drivers of the Earth’s climate. And with many scientists studying possible alternative explanations for the recent temperature increases,[1] it is clear that the IPCC Assessment Reports are far from representing a scientific consensus.
One of the most promising alternatives to the GHG explanation is solar activity. Briefly: solar activity (e.g., solar winds) prevents subatomic particles from entering the Earth’s atmosphere. These particles react with water vapor to form clouds, which shield the Earth from the sun. Fewer particles and therefore fewer clouds equates to more solar radiation being absorbed by the oceans and the Earth’s surface, which could explain the observed temperature increases.
The point of all this is that climatology is a relatively new science. As such, there are many gaps in what is understood about the climate in broad terms. This does not mean that the IPCC should suppress alternative theories or should not incorporate them in to its models so that its general findings remain consistent.[2]
In any event, if the climate’s general dynamics are uncertain then its peculiarities are more unclear.
Unreliability of modeling at sub-continental scales
Existing climate models used for the IPCC process are comprehensive global models designed for mitigation, on large space and time scales. The IPCC concentrates on global averages and freely admits that the smallest region for which the models are useful is the continental scale, about 3,000 miles.[3] On smaller scales the models are not useful.
Members of the scientific community contend that a less coarse spatial resolution, e.g., 2 km or even 100 km is integral to modeling changes for municipal leaders, decision makers, and planners who use climate information as it pertains to water supply, infrastructure, inland transportation, etc.
But the IPCC is not entirely to blame for modeling problems. Even if the reports are based on insufficient and spurious data, they cannot account for technical limitations.
Limitations of computing capability to support modeling
Running a climate simulation model can take days, weeks, even months depending on the number of variables under consideration and the degree of spatial resolution. Further, preparation of the model, i.e., data collection and model construction adds considerably to the time required. But regardless of the credibility of the data and the model’s structure, there appear to be limitations in what computers can generate.
Dr. Alexander MacDonald of National Oceanic and Atmospheric Administration stated in an expert witness testimony before the United States Senate that “[m]odels are constrained by available computing.”[4] Dr. James J. Hack of the National Center for Computational Sciences further bolstered this position as well as others held in this essay in his testimony, noting that “[m]eeting future challenges in climate change science will require qualitatively different levels of scientific understanding, modeling capabilities, and computational infrastructure that are currently available to the climate science community.”[5]
With processing capabilities doubling every 18 months or so it may be several years until computational capacity will meet the needs of the climate modelers today. And as the level of complexity tends to rise with the level of understanding, the computing power may continue to lag behind the science.
Moving Forward
With all of these things said it does not mean that policy makers should not move forward with certain actions. For instance, allocation of public funds towards additional research, model development, and education can be easily implemented and do not carry high shadow costs.
Secondly, while the science may be uncertain and subject to continued debate, efforts undertaken to reduce energy consumption and therefore make our planet cleaner simply make sense and can be easily achieved through education and demand-management, the sciences of which are not as polarizing as the veracity of climate change.
Thirdly, the long-term effects of elevated CO2 concentrations are also unknown. Currently, the concentration is approximately 380 ppm, 30 ppm higher than the historical equilibrium level. So even if GHGs do not contribute to global warming there may be other undesirable effects from higher concentrations that we have yet to recognize.
Finally, whether you agree with the IPCC or not, it seems that we all can agree on the following: Reducing energy consumption saves money and puts less of a strain on scarce energy resources that will only become more expensive. For this reason, non-renewable energy sources must be pursued and proliferated. Not because they will save the planet, but because they may very well save us and ensure the continued existence humanity.
[1] See for example: Usoskin, I. G., M. Schuessler, S. K. Solanki, and K. Mursula (2005), Solar activity, cosmic rays, and Earth’s temperature: A millennium-scale comparison, J. Geophys. Res., 110, A10102, doi:10.1029/2004JA010946.
[3] IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, et al]. Cambridge University Press, Cambridge, United Kingdom, pg. 183
[4]Hearing before the United States Senate, Committee on Commerce, Science, and Transportation “Improving the Capacity of U.S. Climate Modeling for Decisionmakers and End-users.” (May 8, 2008). Available electronically at commerce.senate.gov.
[5] Id
[1] IPCC, 2001: Climate Change 2001: The Physical Science Basis. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, et al]. Cambridge University Press, Cambridge, United Kingdom.
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